Particle sorting device and method

Abstract

The present invention belongs to the field of cell analysis and specifically relates to a particle sorting device and method. The sorting device includes a microfluidic chip having a first flow channel disposed therein; a first group of channels evenly surrounding the first flow channel, with the first inlet and first outlet of each of the first flow channel group connected to the first flow channel; a second group of channels evenly surrounding the first flow channel, with the second inlet of each of the second flow channel group connected to the first flow channel, and a third angle γ between the flow direction of the liquid at the second inlet and the flow direction of the liquid in the first flow channel being an acute angle; the second inlet being disposed between the first inlet and the first outlet; a first chamber connected to the first flow channel and disposed downstream of the first outlet; and an adjustment unit for adjusting the volume of the first chamber. The present invention has advantages such as saving sheath fluid and can be applied in cell analysis.

Description

Technical Field

[0001] The present invention relates to cell analysis, and in particular to a particle sorting device and method. Background Art

[0002] Traditional flow cytometers have many problems, such as large instrument size, complex operation, high-speed sheath fluid and high damage to cells during the injection process.

[0003] After years of development in the field of life sciences, microfluidic technology can now effectively solve problems such as cell manipulation and feature detection, so microfluidic-based flow cytometers and sorters have emerged. Similar to the structure of traditional flow analysis, microfluidic flow cytometry also has focusing and optical detection modules. If there is a sorting function, it will also include a sorting module. The main difference between the two technologies is that the microfluidic chip is a nearly planar structure, and various pipelines are integrated into a single chip, allowing cell analysis to be performed in a closed space. This has many advantages, the most important of which is the avoidance of contamination. Disposable chips avoid contamination between samples, and the closed system eliminates potential aerosol contamination.

[0004] Traditional flow cytometry uses high-speed droplet generation and high-voltage electrical sorting. The high-speed flow of samples and the high voltage applied to the droplets inevitably damage cells, reducing cell viability and severely impacting subsequent experimental results. However, a sorting module integrated into a microfluidic chip can directly sort target cells and particles in liquids, eliminating the need for droplet generation and avoiding the high-voltage, high-speed liquid environment.

[0005] At present, some microfluidic sorting products have appeared, but the existing technical methods still have defects, mainly in two aspects.

[0006] 1. Planar microfluidic sorting chips only achieve fluid focusing in the planar dimension, which causes the sample flow to be planar rather than linear. The poor focusing effect is not conducive to optical detection and affects the instrument CV value.

[0007] 2. The sorting speed is low. Most of these products trigger the sorting force in a direction perpendicular to the sample flow, and the target is sorted by disturbing the fluid. Since it takes some time for the fluid to return to stability after being disturbed in the vertical direction, this greatly affects the sorting time. Summary of the Invention

[0008] In order to solve the deficiencies in the above-mentioned prior art solutions, the present invention provides a microfluidic particle sorting device.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] A particle sorting device includes a microfluidic chip, wherein a first flow channel is provided inside the microfluidic chip for allowing sheath fluid and a sample to flow through; the microfluidic chip is further provided with:

[0011] a first group of flow channels, wherein the plurality of channels of the first group of flow channels uniformly surround the first flow channel, a first inlet and a first outlet of each flow channel in the first group of flow channels are connected to the first flow channel, a first angle α between a flow direction of liquid at the first inlet and a flow direction of liquid in the first flow channel is an acute angle, and a second angle β between a flow direction of liquid at the first outlet and a flow direction of liquid in the first flow channel is an obtuse angle;

[0012] a second group of flow channels, wherein the plurality of channels of the second group of flow channels uniformly surround the first flow channel, a second inlet of each flow channel in the second group of flow channels being connected to the first flow channel, a third angle γ between a flow direction of liquid at the second inlet and a flow direction of liquid in the first flow channel being an acute angle; and the second inlet being located between the first inlet and the first outlet;

[0013] a first chamber, the first chamber being connected to the first flow channel and disposed downstream of the second inlet;

[0014] An adjusting unit is used to adjust the volume of the first chamber.

[0015] The present invention also aims to provide a method for sorting particles using the above-mentioned device, and this object is achieved through the following technical solutions:

[0016] A particle sorting method comprising the following steps:

[0017] (A1) In the first flow channel, the sheath fluid surrounds the sample and flows forward;

[0018] (A2) Part of the outer sheath fluid enters the first set of flow channels, and the remaining sheath fluid continues to wrap the sample and flow forward;

[0019] (A3) Part of the outer sheath fluid enters the second set of flow channels;

[0020] (A4) the sheath fluid in the first group of flow channels flows in the reverse direction from the first outlet into the first flow channels;

[0021] When sorting is required, the volume of the first chamber increases, and the sample in the first flow channel flows through the second inlet and the first outlet in sequence, carrying the sheath fluid flowing from the first outlet in a forward flow and entering the first chamber.

[0022] When sorting is not required, the volume of the first chamber remains unchanged or decreases, the sheath fluid entering the first flow channel from the first outlet flows in the reverse direction and mixes with the sample, and enters the second group of flow channels, and no sample passes through the first outlet.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Use microfluidic chips as sorting flow cells to achieve cross-contamination-free, aerosol-free, low-pressure, and low-damage sorting;

[0025] 2. Sheath fluid is evenly introduced into the outer edge of the first flow channel from two dimensions at different times, achieving microfluidic three-dimensional fluid focusing, achieving better fluid focusing effect, and facilitating optical detection;

[0026] 3. The sheath liquid diversion and reflux fluid switch design helps achieve high-speed sorting without the need for an additional sheath liquid switch, saving sheath liquid;

[0027] 4. Sorting is performed in the direction of sample flow to reduce fluid fluctuations and achieve high-speed sorting. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. Those skilled in the art will readily appreciate that these drawings are merely used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0029] Figure 1 It is a schematic structural diagram of the particle separation device of the present invention;

[0030] Figure 2 It is a partial structural schematic diagram of the particle separation device of the present invention;

[0031] Figure 3 It is a partial structural schematic diagram of the particle sorting device of the present invention.

[0032] In the accompanying drawings, 11-microfluidic chip, 21-fourth group of flow channels, 211-second liquid inlet, 31-sample inlet, 41-first flow channel, 411-first part, 412-second part, 413-third part, 51-first group of flow channels, 511-first inlet, 512-first outlet, 61-second group of flow channels, 611-second inlet, 71-third group of flow channels, 711-second outlet, 712-outer wall, 713-inner wall, 715-first liquid inlet, 81-first chamber, 82-second flow channel, 91-storage chamber. DETAILED DESCRIPTION

[0033] Figure 1-Figure 3The following description describes optional embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. In order to teach the technical solution of the present invention, some conventional aspects have been simplified or omitted. Those skilled in the art will understand that variations or substitutions derived from these embodiments will be within the scope of the present invention. Those skilled in the art will understand that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following optional embodiments, but is limited only by the claims and their equivalents.

[0034] Example 1.

[0035] A particle separation device according to an embodiment of the present invention, such as Figure 1 As shown, it includes a microfluidic chip 11, which is internally provided with:

[0036] The first flow channel 41 is used to allow sheath fluid and sample to flow through.

[0037] The first set of flow channels 51, such as Figure 2 As shown, the multiple channels of the first group of flow channels 51 uniformly surround the first flow channel 41, and the first inlet 511 and the first outlet 512 of each flow channel in the first group of flow channels 51 are connected to the first flow channel 41. The first angle α between the liquid flow direction of the first inlet 511 and the liquid flow direction in the first flow channel 41 is an acute angle, and the second angle β between the liquid flow direction of the first outlet 512 and the liquid flow direction in the first flow channel 41 is an obtuse angle.

[0038] A second group of flow channels 61, multiple channels of the second group of flow channels 61 evenly surround the first flow channel 41, the second inlet 611 of each flow channel in the second group of flow channels 61 is connected to the first flow channel 41, and the third angle γ between the liquid flow direction of the second inlet 611 and the liquid flow direction in the first flow channel 41 is an acute angle; the second inlet 611 is arranged between the first inlet 511 and the first outlet 512.

[0039] The first chamber 81 is connected to the first flow channel 41 and is located downstream of the first outlet 512 .

[0040] An adjusting unit is used to adjust the volume of the first chamber 81 , thereby changing the pressure in the first chamber 81 , and thereby sucking in a sample as needed.

[0041] In order to reduce the complexity of the structure, further, the first group of flow channels 51 includes two flow channels, and the two flow channels are coplanar with the first flow channel 41 and have heart-shaped outer edges.

[0042] The second group of flow channels 61 includes two flow channels, and the two flow channels are coplanar with the first flow channel 41 to form a bell mouth.

[0043] In order to allow the sheath fluid on the outside to wrap the sample on the inside, the first flow channel 41 further includes a first part 411 located upstream of the first inlet 511, a second part 412 between the first inlet 511 and the first outlet 512, and a third part 413 downstream of the first outlet 512, wherein the inner diameter of the first part 411 is greater than the inner diameter of the second part 412 and the inner diameter of the third part 413, and the third part 413 is connected to the first chamber 81.

[0044] In order to stably adjust the volume of the first chamber 81, the adjusting unit further includes:

[0045] The deformation module and the film isolate the inside and outside of the first chamber 81. The deformation module is arranged outside the first chamber 81 and connected to the film.

[0046] In order to ensure that the sheath fluid wraps the sample stably, further, γ>α>(β-90°), 30°≤α≤60°.

[0047] To better wrap the sample, e.g. Figure 3 As shown, the microfluidic chip 11 is further provided with:

[0048] The third group of flow channels 71, the multiple channels of the third group of flow channels 71 are all connected to the first liquid inlet 715 and evenly surround the first flow channel 41, the second outlet 711 of each flow channel in the third group of flow channels 71 is connected to the first flow channel 41 upstream of the first inlet 511, and the fourth angle between the liquid flow direction of the second outlet 711 and the liquid flow direction in the first flow channel 41 is an acute angle.

[0049] The outer wall 712 and the inner wall 713 of the second outlet 711 are respectively curved and tangent to the outer wall of the first flow channel 41. The curvature radius of the outer wall 712 is 30mm-40mm, and the central angle d is 10 degrees-30 degrees. The curvature radius of the inner wall 713 is 5mm-20mm, and the central angle e is 10 degrees-30 degrees, and d>e.

[0050] The distance between the center of the central angle d and the center of the central angle e on the vertical point of the first flow channel 41 is 5 mm-10 mm.

[0051] The particle sorting method according to the embodiment of the present invention, that is, the operating method of the particle sorting device according to the embodiment of the present invention, includes the following steps:

[0052] (A1) In the first flow channel 41 , the sheath fluid surrounds the sample and flows in the forward direction.

[0053] (A2) Part of the outer sheath fluid enters the first group of flow channels 51, and the remaining sheath fluid continues to wrap the sample and flow forward.

[0054] (A3) Part of the outer sheath fluid enters the second group of flow channels 61 .

[0055] (A4) The sheath fluid in the first group of flow channels 51 flows in the reverse direction from the first outlet 512 into the first flow channel 41 .

[0056] When sorting is required, the volume of the first chamber 81 increases, and the sample in the first flow channel 41 flows through the second inlet 611 and the first outlet 512 in sequence, carrying the sheath fluid flowing from the first outlet 512 in a forward flow and entering the first chamber 81 .

[0057] When sorting is not required, the volume of the first chamber 81 remains unchanged or decreases, the sheath fluid entering the first flow channel 41 from the first outlet 512 flows in the reverse direction and mixes with the sample, and enters the second group of flow channels 61 , and no sample passes through the first outlet 512 .

[0058] In order to wrap the sample to focus the sample, e.g. Figure 3 As shown, in step (A1), the sheath fluid enters the first flow channel 41 in the following manner:

[0059] The sheath fluid enters from the first liquid inlet 715 and then enters the first flow channel 41 from the multiple channels of the third group of flow channels 71, wraps around the sample and flows in the forward direction.

[0060] The multiple channels of the third group of flow channels 71 evenly surround the first flow channel 41, and the second outlet 711 of each flow channel in the third group of flow channels 71 is connected to the first flow channel 41 upstream of the first inlet 511. The fourth angle between the liquid flow direction of the second outlet 711 and the liquid flow direction in the first flow channel 41 is an acute angle.

[0061] The outer wall 712 and the inner wall 713 of the second outlet 711 are respectively curved and tangent to the outer wall of the first flow channel 41. The curvature radius of the outer wall 712 is 30mm-40mm, and the central angle d is 10 degrees-30 degrees. The curvature radius of the inner wall 713 is 5mm-20mm, and the central angle e is 10 degrees-30 degrees, and d>e.

[0062] The distance between the center of the central angle d and the center of the central angle e on the vertical point of the first flow channel 41 is 5 mm-10 mm.

[0063] In order to stably adjust the volume of the first chamber 81, the volume of the first chamber 81 is further adjusted as follows:

[0064] The deformation module pushes the film in the first chamber 81 to move back and forth, and the volume of the first chamber 81 switches between increasing and decreasing.

[0065] Example 2.

[0066] An example of application of the particle sorting device and method in Example 1 of the present invention in cell sorting.

[0067] In this application example, if Figure 1 As shown, the first flow channel 41 includes a linear first portion 411 (75 μm in horizontal width), a second portion 412 (50 μm in horizontal width), and a third portion 413 (25 μm in horizontal width). The third portion 413 sequentially connects the first chamber 81, the second flow channel 82, and the storage chamber 91.

[0068] like Figure 2 As shown, the first group of flow channels 51 includes two channels coplanar (horizontally) with the first flow channel 41, with heart-shaped outer edges. These two channels symmetrically and evenly surround the first flow channel 41. The first inlet 511 and first outlet 512 of each flow channel are both connected to the first flow channel 41. The first angle α between the liquid flow direction of the first inlet 511 and the liquid flow direction within the first flow channel 41 is 35 degrees, and the second angle β between the liquid flow direction of the first outlet 512 and the liquid flow direction within the first flow channel 41 is 120 degrees. The area between the first inlet 511 and the first outlet 512 forms the second portion 412 of the first flow channel 41.

[0069] The second group of flow channels 61 includes two channels coplanar (horizontally) with the first flow channel 41, forming an ω-shaped structure. The two channels symmetrically and evenly surround the second portion 412 of the first flow channel 41. The second inlet 611 of each flow channel in the second group of flow channels 61 connects to the first flow channel 41. The third angle γ between the liquid flow direction of the second inlet 611 and the liquid flow direction in the first flow channel 41 is 60 degrees, satisfying the condition γ > α > (β - 90°). The second inlet 611 is located between the first inlet 511 and the first outlet 512. The outlet of the second group of flow channels 61 connects to the waste liquid tank.

[0070] like Figure 3 As shown, the third group of flow channels 71 includes a first liquid inlet 715 and two arcuate channels arranged horizontally within the microfluidic chip 11, uniformly surrounding the first flow channel 41. The second outlets 711 of the arcuate flow channels are both connected to the first flow channel 41 (i.e., the first portion 411) upstream of the first inlet 511. The fourth angle between the liquid flow direction of the second outlets 711 and the liquid flow direction within the first flow channel 41 is an acute angle.

[0071] The outer wall 712 and the inner wall 713 of the second outlet 711 are curved respectively and tangent to the outer wall of the first flow channel 41. The curvature radius of the outer wall 712 is 30 mm-40 mm, such as 33.4 mm, and the central angle d is 10 degrees-30 degrees, such as 20 degrees. The curvature radius of the inner wall 713 is 5 mm-20 mm, such as 12.6 mm, and the central angle e is 10 degrees-30 degrees, such as 18 degrees, and d>e.

[0072] The distance between the center of the central angle d and the center of the central angle e on the vertical point of the first flow channel 41 is 5 mm-10 mm, such as 6.5 mm.

[0073] The fourth group of flow channels 21 includes a second liquid inlet 211 and two arc-shaped channels perpendicular to the horizontal plane and arranged in the microfluidic chip 11 , symmetrically and evenly surrounding the first portion 411 of the first flow channel 41 .

[0074] The cross section of each of the flow channels perpendicular to the central axis thereof is rectangular.

[0075] The particle sorting method according to the embodiment of the present invention, that is, the operating method of the particle sorting device according to the embodiment of the present invention, includes the following steps:

[0076] (A1) First, a sample enters the first portion 411 through the sample inlet 31 .

[0077] Then, the sheath liquid that enters the first portion 411 through the second liquid inlet 211 and the fourth group of flow channels 21 in sequence surrounds the sample and wraps the sample (in a cross section perpendicular to the central axis of the first portion 411 ).

[0078] Afterwards, the sheath fluid that enters the first portion 411 through the first liquid inlet 715 and the third set of flow channels 71 in sequence surrounds the sample, wraps the sample (in the cross section perpendicular to the central axis of the first portion 411 ), and flows forward in the first flow channel 41 .

[0079] (A2) Part of the outer sheath fluid enters the first group of flow channels 51 , and the remaining sheath fluid continues to wrap the sample and flows forward in the second portion 412 .

[0080] (A3) Part of the outer sheath fluid enters the second group of flow channels 61 .

[0081] (A4) The sheath fluid in the first group of flow channels 51 flows in the reverse direction from the first outlet 512 into the first flow channel 41 .

[0082] When sorting is required, the piezoelectric crystal drives the film to move, causing the volume of the first chamber 81 to increase, and the sample wrapped by the sheath fluid in the second part 412 flows through the second inlet 611 and the first outlet 512 in turn, carrying the sheath fluid flowing in from the first outlet 512 in a forward flow, enters the first chamber 81, and then enters the storage chamber 91 through the second flow channel 82.

[0083] When sorting is not required, the volume of the first chamber 81 remains unchanged or becomes smaller, the sheath fluid entering the first flow channel 41 from the first outlet 512 flows in the opposite direction and mixes with the sample in the second part 412 and enters the second group of flow channels 61, and no sample enters the third part 413.

[0084] Example 3.

[0085] According to the application of the particle sorting device and method in Example 1 of the present invention in cell sorting, the difference from Example 2 is that:

[0086] 1. Increase the volume of the first chamber 81.

[0087] 2. Storage room 91 is no longer provided.

Claims

1. A particle sorting device, comprising a microfluidic chip, wherein a first flow channel is provided inside the microfluidic chip, allowing sheath fluid and a sample to flow through, wherein the sheath fluid surrounds the sample in the first flow channel; The microfluidic chip is further provided with: a first group of flow channels, wherein the plurality of channels of the first group of flow channels uniformly surround the first flow channel, a first inlet and a first outlet of each flow channel in the first group of flow channels are connected to the first flow channel, a first angle α between a flow direction of liquid at the first inlet and a flow direction of liquid in the first flow channel is an acute angle, and a second angle β between a flow direction of liquid at the first outlet and a flow direction of liquid in the first flow channel is an obtuse angle; a second group of flow channels, wherein the plurality of channels of the second group of flow channels uniformly surround the first flow channel, a second inlet of each flow channel in the second group of flow channels being connected to the first flow channel, a third angle γ between a flow direction of liquid at the second inlet and a flow direction of liquid in the first flow channel being an acute angle; and the second inlet being located between the first inlet and the first outlet; a first chamber, the first chamber being connected to the first flow channel and disposed downstream of the first outlet; An adjusting unit is used to adjust the volume of the first chamber.

2. The particle sorting device according to claim 1, characterized in that: The first group of flow channels includes two flow channels, the two flow channels are coplanar with the first flow channel, and the outer edges are heart-shaped; The second group of flow channels includes two flow channels, and the two flow channels are coplanar with the first flow channel to form a bell mouth.

3. The particle sorting device according to claim 1, characterized in that: The first flow channel includes a first part located upstream of the first inlet, a second part between the first inlet and the first outlet, and a third part located downstream of the first outlet, wherein the inner diameter of the first part is greater than the inner diameter of the second part and greater than the inner diameter of the third part, and the third part is connected to the first chamber.

4. The particle sorting device according to claim 1, characterized in that: The adjustment unit includes: A deformation module and a film, wherein the film isolates the inside and outside of the first chamber, and the deformation module is arranged outside the first chamber and connected to the film.

5. The particle sorting device according to claim 1, characterized in that: γ>α>(β-90°), 30°≤α≤60°.

6. The particle sorting device according to claim 1, characterized in that: The microfluidic chip is further provided with: a third group of flow channels, the third group of flow channels comprising a first liquid inlet and a plurality of channels, the plurality of channels being connected to the first liquid inlet and uniformly surrounding the first flow channel, the second outlet of each flow channel in the third group of flow channels being connected to the first flow channel upstream of the first inlet, and a fourth angle between a liquid flow direction at the second outlet and a liquid flow direction in the first flow channel being an acute angle; The outer wall and inner wall of the second outlet are respectively curved and tangent to the outer wall of the first flow channel. The curvature radius of the outer wall is 30 mm to 40 mm, and the central angle d is 10 degrees to 30 degrees. The curvature radius of the inner wall is 5 mm to 20 mm, and the central angle e is 10 degrees to 30 degrees, where d>e. The distance between the center of the central angle d and the vertical point on the first flow channel is 5mm-10mm; The fourth group of flow channels includes a second liquid inlet and an arcuate channel perpendicular to the horizontal plane where the second group of flow channels and the first flow channel are located. The arcuate channel uniformly surrounds the first flow channel, and the second liquid inlet connects the arcuate channel and the first flow channel.

7. The particle separation method implemented by the particle separation device according to claim 1, characterized in that: The particle sorting method comprises the following steps: A1. In the first flow channel, the sheath fluid surrounds the sample and flows forward. A2. Part of the outer sheath fluid enters the first set of flow channels, and the remaining sheath fluid continues to wrap the sample and flow forward; A3. Part of the outer sheath fluid enters the second set of flow channels; A4. The sheath fluid in the first set of flow channels enters the first flow channel in the reverse direction from the first outlet; When sorting is required, the volume of the first chamber increases, and the sample in the first flow channel flows through the second inlet and the first outlet in sequence, carrying the sheath fluid flowing from the first outlet in a forward flow and entering the first chamber; When sorting is not required, the volume of the first chamber remains unchanged or decreases, the sheath fluid entering the first flow channel from the first outlet flows in the reverse direction and mixes with the sample, and enters the second group of flow channels, and no sample passes through the first outlet.

8. The particle separation method according to claim 7, characterized in that: The microfluidic chip is further provided with: a third group of flow channels, the third group of flow channels comprising a first liquid inlet and a plurality of channels, the plurality of channels uniformly surrounding the first flow channel, the second outlet of each channel in the third group of flow channels being connected to the first flow channel upstream of the first inlet, and a fourth angle between a liquid flow direction at the first outlet and a liquid flow direction in the first flow channel being an acute angle; The outer wall and inner wall of the second outlet are respectively curved and tangent to the outer wall of the first flow channel. The curvature radius of the outer wall is 30 mm to 40 mm, and the central angle d is 10 degrees to 30 degrees. The curvature radius of the inner wall is 5 mm to 20 mm, and the central angle e is 10 degrees to 30 degrees, where d>e. The distance between the center of the central angle d and the vertical point on the first flow channel is 5mm-10mm; a fourth group of flow channels, the fourth group of flow channels comprising a second liquid inlet and an arcuate channel perpendicular to a horizontal plane where the second group of flow channels and the first flow channel are located, the arcuate channel uniformly surrounding the first flow channel, the second liquid inlet communicating with the arcuate channel and the first flow channel; In step A1, the sheath fluid enters the first flow channel in the following manner: The sheath liquid enters the first flow channel through the second liquid inlet and the arc-shaped channel in sequence, surrounds the sample, and wraps the sample; Afterwards, the sheath fluid enters from the first liquid inlet, and then enters the first flow channel from multiple channels of the third group of flow channels, wraps around the sample and flows forward.

9. The particle separation method according to claim 7, characterized in that: The adjustment unit includes a deformation module and a film, the film isolating the inside and outside of the first chamber, and the deformation module is arranged outside the first chamber and connected to the film; The volume of the first chamber is adjusted as follows: The deformation module pushes the film in the first chamber to move back and forth, and the volume of the first chamber switches between increasing and decreasing.

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